KeepExisting Element (DTA)
Applies to: 
SQL Server
Specifies the physical design structures (indexes, indexed views, or partitioning) that Database Engine Tuning Advisor must retain when generating its recommendation.
Syntax
<DTAInput>
...code removed...
<TuningOptions>
<KeepExisting>...</KeepExisting>
Element Characteristics
| Characteristic | Description |
|---|---|
| Data type and length | string, length limit enforced by the server. |
| Allowed values | NONE No existing structures. ALL All existing structures. ALIGNED All partition-aligned structures. CL_IDX All clustered indexes on tables. IDX All clustered and nonclustered indexes on tables. Use only one of these values with this element. |
| Default value | None. |
| Occurrence | Optional. Can use only once for each TuningOptions element. |
Element Relationships
| Relationship | Elements |
|---|---|
| Parent element | TuningOptions Element (DTA) |
| Child elements | None. |
Example
For a usage example of this element, see the Simple XML Input File Sample (DTA).